First-line Palliative Chemotherapy for Colorectal Cancer: a Population-based Analysis of Delivery and Outcomes in a Single-payer Health System

AIMS

Clinical practice guidelines recommend palliative chemotherapy for most patients with metastatic colorectal cancer. However, outcomes observed in the real world compared with patients enrolled in clinical trials have not been sufficiently described. The objective of this study was to evaluate the delivery and outcomes of first-line palliative chemotherapy administered to patients with colorectal cancer in routine clinical practice compared with clinical trials.

MATERIALS AND METHODS

Using linked health administrative data, we carried out a retrospective population-level cohort study on patients diagnosed with colorectal cancer in Ontario, Canada from 2010 to 2019. Patient, disease and treatment characteristics were summarised. The primary outcome was median overall survival, stratified by treatment prescribed and age. Demographics and outcomes in this real-world population were compared with those from pivotal clinical trials. A multivariable Cox regression model reporting hazard ratios and 95% confidence intervals was used to determine factors associated with survival in patients receiving systemic treatment.

RESULTS

We identified 70 987 patients with a new diagnosis of colorectal cancer, of which 4613 received first-line chemotherapy for unresectable locally advanced or metastatic disease and formed the study cohort. Fifty-eight per cent were male and the mean age was 63 years. Most had colon cancer (69%), at least one comorbidity (73%) and lived in an urban location (79%). Less than half (47%) had surgery after diagnosis. The most common regimen prescribed was folinic acid, 5-fluorouracil and irinotecan (FOLFIRI) with bevacizumab or epidermal growth factor receptor inhibitors (EGFRi; n = 2784, 60%). Among all treated patients, the median overall survival was 17.1 months, with survival difference by regimen [median overall survival 18.3 for FOLFIRI with bevacizumab or EGFRi, 19.6 for folinic acid, 5-fluorouracil and oxaliplatin (FOLFOX)/capecitabine, oxaliplatin (XELOX) with bevacizumab or EGFRi, 13.6 for FOLFIRI alone and 7.8 for 5-fluorouracil or capecitabine]. Patients aged >80 years were most likely to have received single-agent 5-fluorouracil or capecitabine, and had inferior overall survival compared with their younger counterparts. Compared with pivotal clinical trials, patients in the real world had inferior overall survival outcomes despite similar demographic characteristics (including age and sex).

CONCLUSIONS

In this real-world population-based analysis of patients receiving first-line chemotherapy for unresectable locally advanced or metastatic colorectal cancer, survival outcomes were inferior to those reported in randomised trials despite similarities in age and sex. This information can be used when counselling patients in routine practice about expected outcomes.

Integrated Virtual Care for Irritable Bowel Syndrome: A Qualitative Study

Irritable bowel syndrome (IBS) is a condition that affects approximately one in 10 people in the United States (Defrees & Bailey, 2017). Despite the high prevalence of IBS, the medical community struggles to effectively understand, diagnose, and treat this disorder (Ankersen et al., 2021). In recent years, an increasing number of health-tech companies have emerged to offer integrated treatment of IBS via telemedicine. This pilot study explores the patient experience of virtual, multidisciplinary IBS care through a U.S.-based company, Oshi Health. Semistructured interviews were conducted followed by thematic analysis to identify commonalities between patient experience and perspective (Van Manen, 2014). Overarching themes were identified as follows: loss of the grocer, a broken system, and the power of self-trust. Although several limitations exist, including small sample size, the study offers insight into the experience of telemedicine services for IBS and provides a framework for future research.

1121 Single Use Nasal Endoscopes – A Review of The Cost and Organisational Implications Based on Department Size

Aim

Single use nasal endoscopes have become increasingly popular since the COVID-19 pandemic. By avoiding the risk of cross contamination and reducing exposure by eliminating the need for re-processing, the disposable scopes have clear safety benefits. Despite ENT UK guidelines recommending that disposable nasal endoscopes be available in every department for use in emergencies, they have often been considered prohibitively expensive. The aim of this study was to analyse the costs associated with traditional nasal endoscopes and compare them to the single use scopes.

Method

A micro costing exercise was undertaken in three ENT departments: 2 university hospitals, and 1 district general hospital. The outcomes were compared and discussed with relation to the logistics of the departments, as well as organizational considerations.

Results

Cost per procedure varied according to the reprocessing methods used in the different departments. The cost of the disposable nasal endoscopes appears high, however there are many hidden costs associated with the traditional scopes, which can be difficult to quantify accurately.

Conclusions

Although disposable endoscopes appear costly, reprocessing and frequent repairs required for re-usable scopes account for the comparable cost per procedure. The high risk of COVID-19 transmission from examining the upper aerodigestive tract means that the safety benefits bear more weight in the current climate. However, concerns regarding environmental impact, image quality and storage of examinations also need to be considered.

Metformin with neoadjuvant chemoradiation to improve pathologic response in rectal cancer: A pilot phase I/II trial

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A prospective pilot phase I/II study on metformin given concurrently with neoadjuvant chemoradiation (CRT) in non-diabetic rectal cancer patients.

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Three patients had a clinical complete response (cCR) and did not have surgical resection.

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Of the 12 patients who underwent surgery, there were two pCRs. For the combined pCR/cCR rate of 33% (95% CI 19–47%), a total of 85 patients will be required to yield a 95% CI with a 10% margin of error.

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These pilot results are encouraging, and will serve to refine the design and conduct of a future phase 2 trial to determine whether adding metformin to CRT improves pCR/cCR rates.

Purpose

Neoadjuvant radiotherapy with or without chemotherapy decreases the risk of local recurrence after surgery for rectal cancer. Emerging data suggest that diabetic patients on metformin may have improved cancer outcome after radiotherapy. A single institutional pilot study was performed to determine if metformin given concurrently with long course chemoradiation (CRT) may improve pathologic complete response (pCR) in non-diabetic rectal cancer patients. The study was designed to construct a confidence interval (CI) for the pCR rate to determine the sample size for a phase 2 trial.

Methods

Non-diabetic patients with biopsy confirmed rectal cancer deemed candidates for long course neoadjuvant CRT were invited to participate. Radiation consisted of 50.4 Gy in 28 daily fractions with concurrent daily capecitabine (825 mg/m² twice daily). Participants self-administered metformin (500 mg of twice daily) 2 weeks prior to, during and for 4 weeks after CRT.

Results

A total of 16 patients were accrued. One patient withdrew from the study. Only grade 1 or 2 adverse events were observed. Three patients had a clinical complete response (cCR) and did not undergo surgery. Of the 12 patients who underwent surgery, there were two pCRs. For the combined pCR/cCR rate of 33% (95% CI 19–47%), a total of 85 patients will be required to yield a 95% CI with a 10% margin of error.

Conclusions

Adding metformin to neoadjuvant CRT for rectal cancer does not appear to enhance toxicities. These results will be used to refine the design and conduct of a future phase 2 trial to determine whether adding metformin to CRT improves pCR/cCR rates.

Clinical applications of artificial intelligence and machine learning-based methods in inflammatory bowel disease

Our objective was to review and exemplify how selected applications of artificial intelligence (AI) might facilitate and improve inflammatory bowel disease (IBD) care and to identify gaps for future work in this field. IBD is highly complex and associated with significant variation in care and outcomes. The application of AI to IBD has the potential to reduce variation in healthcare delivery and improve quality of care. AI refers to the ability of machines to mimic human intelligence. The range of AI's ability to perform tasks that would normally require human intelligence varies from prediction to complex decision-making that more closely resembles human thought. Clinical applications of AI have been applied to study pathogenesis, diagnosis, and patient prognosis in IBD. Despite these advancements, AI in IBD is in its early development and has tremendous potential to transform future care.

A systematic review and network meta-analysis of second-line therapy in hepatocellular carcinoma

Background

In patients with advanced hepatocellular carcinoma (hcc) following sorafenib failure, it is unclear which treatment is most efficacious, as treatments in the second-line setting have not been directly compared and no standard therapy exists. This systematic review and network meta-analysis (nma) aimed to compare the clinical benefits and toxicities of these treatments.

Methods

A systematic review of randomized controlled trials (rcts) was conducted to identify phase iii rcts in advanced hcc following sorafenib failure. Baseline characteristics and outcomes of placebo were examined for heterogeneity. Primary outcomes of interest were extracted for results, including overall survival (os), progression-free survival (pfs), objective response rate (orr), grade 3/4 toxicities, and subgroups. An nma was conducted to compare both drugs through the intermediate placebo. Comparisons were expressed as hazard ratios (hrs) for os and pfs, and as risk difference (rd) for orr and toxicities. Subgroup analyses for os and pfs were also performed.

Results

Two rcts were identified (1280 patients) and compared through an indirect network; celestial (cabozantinib vs. placebo) and resorce (regorafenib vs. placebo). Baseline characteristics of patients in both trials were similar. Both trials also had similar placebo outcomes. Cabozantinib, compared with regorafenib, showed similar os [hazard ratio (hr): 1.21; 95% confidence interval (ci): 0.90 to 1.62], pfs (hr: 1.02; 95% ci: 0.78 to 1.34) and orr (-3.0%; 95% ci: -7.6% to 1.7%). Both treatments showed similar toxicities, but there were marginally higher risks of grade 3/4 hand-foot syndrome (5%; 95% ci: 0.1% to 9.8%), diarrhea (4.8%; 95% ci: 1.1% to 8.5%), and anorexia (4.4%; 95% ci: 0.8% to 8.0%) for cabozantinib. Subgroup results for os and pfs were consistent with overall results.

Conclusions

Overall, this nma determined that cabozantinib and regorafenib have similar clinical benefits and toxicities for second-line hcc.

A retrospective observational study to estimate the attrition of patients across lines of systemic treatment for metastatic colorectal cancer in Canada

Background

Selection and sequencing of treatment regimens for individual patients with metastatic colorectal cancer (mcrc) is driven by maintaining reasonable quality of life and extending survival, as well as by access to and cost of therapies. The objectives of the present study were to describe, for patients with mcrc, attrition across lines of systemic therapy, patterns of therapy and their timing, and KRAS status.

Methods

A retrospective chart review at 6 Canadian academic centres included sequential patients who were diagnosed with mcrc from 1 January 2009 onward and who initiated first-line systemic treatment for mcrc between 1 January and 31 December 2009. Death was included as a competing risk in the analysis.

Results

The analysis included 200 patients who started first-line therapy. The proportions of patients who started second-, third-, and fourth-line systemic therapy were 70%, 30%, and 15% respectively. Chemotherapy plus bevacizumab was the most common first-line combination (66%). The most common first-line regimen was folfiri plus bevacizumab. KRAS testing was performed in 103 patients (52%), and 38 of 68 patients (56%, 19% overall) with confirmed KRAS wild-type tumours received an epidermal growth factor receptor inhibitor (egfri), which was more common in later lines. Most KRAS testing occurred after initiation of second-line therapy.

Conclusions

In the modern treatment era, a high proportion of patients receive at least two lines of therapy for mcrc, but only 19% receive egfri therapy. Earlier KRAS testing and therapy with an egfri might allow a greater proportion of patients to access all 5 active treatment agents.

Eastern Canadian Gastrointestinal Cancer Consensus Conference 2018

The annual Eastern Canadian Gastrointestinal Cancer Consensus Conference was held in Halifax, Nova Scotia, 20-22 September 2018. Experts in radiation oncology, medical oncology, surgical oncology, and pathology who are involved in the management of patients with gastrointestinal malignancies participated in presentations and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses multiple topics in the management of pancreatic cancer, pancreatic neuroendocrine tumours, hepatocellular cancer, and rectal and colon cancer, including ■ surgical management of pancreatic adenocarcinoma,■ adjuvant and metastatic systemic therapy options in pancreatic adenocarcinoma,■ the role of radiotherapy in the management of pancreatic adenocarcinoma,■ systemic therapy in pancreatic neuroendocrine tumours,■ updates in systemic therapy for patients with advanced hepatocellular carcinoma,■ optimum duration of adjuvant systemic therapy for colorectal cancer, and■ sequence of therapy in oligometastatic colorectal cancer.

Bayesian model of disease progression in GNE myopathy

One Sentence Summary: A Bayesian repeated measures model based on quantitative muscle strength data from a prospective Natural History Study was developed to determine disease progression and design clinical trials for GNE myopathy, a rare and slowly progressive muscle disease. GNE myopathy is a rare muscle disease characterized by slowly progressive weakness and atrophy of skeletal muscles. To address the significant challenges of defining the natural history and designing clinical trials for GNE myopathy, we developed a Bayesian latent variable repeated measures model to determine disease progression. The model is based on longitudinal quantitative muscle strength data collected as part of a prospective Natural History Study. The GNE Myopathy Progression Model provides an understanding of disease progression that would have otherwise required a natural history of unfeasible duration. "Disease age," the model-generated measure of disease progression, highly correlates with a variety of clinical, functional and patient-reported outcomes. With the incorporation of a treatment effect parameter to the GNE Disease Progression Model, we describe a novel GNE Myopathy Disease Modification Analysis that significantly increases power and reduces the number of subjects required to test the effectiveness of novel therapies when compared to more traditional analysis methods. The GNE Myopathy Disease Progression Model and Disease Modification Analysis can be applied to muscle diseases with prospectively collected muscle strength data, and a variety of rare and slowly progressive diseases.

Eastern Canadian Colorectal Cancer Consensus Conference 2017

The annual Eastern Canadian Gastrointestinal Cancer Consensus Conference 2017 was held in St. John's, Newfoundland and Labrador, 28-30 September. Experts in radiation oncology, medical oncology, surgical oncology, and cancer genetics who are involved in the management of patients with gastrointestinal malignancies participated in presentations and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses multiple topics in the management of gastric, rectal, and colon cancer, including ■ identification and management of hereditary gastric and colorectal cancer (crc);■ palliative systemic therapy for metastatic gastric cancer;■ optimum duration of preoperative radiation in rectal cancer-that is, short- compared with long-course radiation;■ management options for peritoneal carcinomatosis in crc;■ implications of tumour location for treatment and prognosis in crc; and■ new molecular markers in crc.

The predictive effect of primary tumour location in the treatment of metastatic colorectal cancer: a Canadian consensus statement

In recently published data, the predictive value of primary tumour location for the treatment of metastatic colorectal cancer with available biologic therapies has been explored. Recognizing the potential effect of those data on clinical practice, we convened a meeting of Canadian experts who treat metastatic colorectal cancer to develop a set of national, evidence-based treatment guidelines based on primary tumour location. This report summarizes the relevant evidence and presents the consensus recommendations of those experts.

Intermittent mydriasis associated with carotid vascular occlusion

PurposeTo describe two cases of stereotyped, intermittent, neurologically isolated, unilateral mydriasis in patients with a history of acquired internal carotid artery (ICA) occlusive disease on the ipsilateral side.PatientsTwo patients with intermittent mydriasis.MethodsCase Series.ResultsCase one: A 78-year-old man experienced 10 episodes of intermittent, unilateral, and painless mydriasis in the left eye and had 100% occlusion of the left ICA artery due to atherosclerotic disease. Case two: A 26-year-old woman with history of migraine developed new painless, intermittent episodes of unilateral mydriasis after sustaining chest trauma and was diagnosed with subsequent dissection and 65% occlusion of the ipsilateral ICA. Neither patient developed permanent anisocoria.ConclusionBenign episodic unilateral mydriasis (BEUM) typically presents in young women with a history of migraine. To our knowledge, these are the first cases of episodic, unilateral, neurologically isolated mydriasis associated with occlusive disease of the ICA in the English language ophthalmic literature. We hypothesize that transient dysfunction of the autonomic nervous system related to the ICA disease may account for the intermittent mydriatic episodes in these patients and we recommend consideration for imaging of the ICA in patients with atypical features for BEUM (for example, old age or males, non-isolated mydriasis, or recent trauma).

Advanced Methods for Dose and Regimen Finding During Drug Development: Summary of the EMA/EFPIA Workshop on Dose Finding (London 4-5 December 2014)

Inadequate dose selection for confirmatory trials is currently still one of the most challenging issues in drug development, as illustrated by high rates of late‐stage attritions in clinical development and postmarketing commitments required by regulatory institutions. In an effort to shift the current paradigm in dose and regimen selection and highlight the availability and usefulness of well‐established and regulatory‐acceptable methods, the European Medicines Agency (EMA) in collaboration with the European Federation of Pharmaceutical Industries Association (EFPIA) hosted a multistakeholder workshop on dose finding (London 4–5 December 2014). Some methodologies that could constitute a toolkit for drug developers and regulators were presented. These methods are described in the present report: they include five advanced methods for data analysis (empirical regression models, pharmacometrics models, quantitative systems pharmacology models, MCP‐Mod, and model averaging) and three methods for study design optimization (Fisher information matrix (FIM)‐based methods, clinical trial simulations, and adaptive studies). Pairwise comparisons were also discussed during the workshop; however, mostly for historical reasons. This paper discusses the added value and limitations of these methods as well as challenges for their implementation. Some applications in different therapeutic areas are also summarized, in line with the discussions at the workshop. There was agreement at the workshop on the fact that selection of dose for phase III is an estimation problem and should not be addressed via hypothesis testing. Dose selection for phase III trials should be informed by well‐designed dose‐finding studies; however, the specific choice of method(s) will depend on several aspects and it is not possible to recommend a generalized decision tree. There are many valuable methods available, the methods are not mutually exclusive, and they should be used in conjunction to ensure a scientifically rigorous understanding of the dosing rationale.

Randomized phase II study of modified FOLFOX-6 in combination with ramucirumab or icrucumab as second-line therapy in patients with metastatic colorectal cancer after disease progression on first-line irinotecan-based therapy

BACKGROUND

Icrucumab and ramucirumab are recombinant human IgG1 monoclonal antibodies that bind VEGF receptors 1 and 2 (VEGFR-1 and -2), respectively. This randomized phase II study evaluated the antitumor activity and safety of icrucumab and ramucirumab each in combination with mFOLFOX-6 in patients with metastatic colorectal cancer after disease progression on first-line therapy with a fluoropyrimidine and irinotecan.

PATIENTS AND METHODS

Eligible patients were randomly assigned to receive mFOLFOX-6 alone (mFOLFOX-6) or in combination with ramucirumab 8 mg/kg IV (RAM+mFOLFOX-6) or icrucumab 15 mg/kg IV (ICR+mFOLFOX-6) every 2 weeks. Randomization was stratified by prior bevacizumab therapy. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), tumor response, safety, and PK.

RESULTS

In total, 158 patients were randomized, but only 153 received treatment (49 on mFOLFOX-6, 52 on RAM+mFOLFOX-6, and 52 on ICR+mFOLFOX-6). Median PFS was 18.4 weeks on mFOLFOX-6, 21.4 weeks on RAM+mFOLFOX-6, and 15.9 weeks on ICR+mFOLFOX-6 (RAM+mFOLFOX-6 versus mFOLFOX-6, stratified hazard ratio [HR] 1.116 [95% CI 0.713-1.745], P = 0.623; ICR+mFOLFOX-6 versus mFOLFOX-6, stratified HR 1.603 [95% CI 1.011-2.543], P = 0.044). Median survival was 53.6 weeks on mFOLFOX-6, 41.7 weeks on RAM+mFOLFOX-6, and 42.0 weeks on ICR+mFOLFOX-6. The most frequent adverse events reported on the ramucirumab arm (RAM+mFOLFOX-6) were fatigue, nausea, and peripheral sensory neuropathy; those on the icrucumab arm (ICR+mFOLFOX-6) were fatigue, diarrhea, and peripheral sensory neuropathy. Grade ≥3 serious adverse events occurred at comparable frequency across arms.

CONCLUSIONS

In this study population, combining ramucirumab or icrucumab with mFOLFOX-6 did not achieve the predetermined improvement in PFS.

CLINICALTRIALSGOV

NCT01111604.

Eastern Canadian Colorectal Cancer Consensus Conference 2013: Emerging Therapies in the Treatment of Pancreatic, Rectal, and Colorectal Cancers

The annual Eastern Canadian Colorectal Cancer Consensus Conference held in Montreal, Quebec, 17–19 October 2013, marked the 10-year anniversary of this meeting that is attended by leaders in medical, radiation, and surgical oncology. The goal of the attendees is to improve the care of patients affected by gastrointestinal malignancies. Topics discussed during the conference included pancreatic cancer, rectal cancer, and metastatic colorectal cancer.

The Thermosiphon Cooling System of the ATLAS Experiment at the CERN Large Hadron Collider

The silicon tracker of the ATLAS experiment at CERN Large Hadron Collider will operate around –15°C to minimize the effects of radiation damage. The present cooling system is based on a conventional evaporative circuit, removing around 60 kW of heat dissipated by the silicon sensors and their local electronics. The compressors in the present circuit have proved less reliable than originally hoped, and will be replaced with a thermosiphon. The working principle of the thermosiphon uses gravity to circulate the coolant without any mechanical components (compressors or pumps) in the primary coolant circuit. The fluorocarbon coolant will be condensed at a temperature and pressure lower than those in the on-detector evaporators, but at a higher altitude, taking advantage of the 92 m height difference between the underground experiment and the services located on the surface. An extensive campaign of tests, detailed in this paper, was performed using two small-scale thermosiphon systems. These tests confirmed the design specifications of the full-scale plant and demonstrated operation over the temperature range required for ATLAS. During the testing phase the system has demonstrated unattended long-term stable running over a period of several weeks. The commissioning of the full scale thermosiphon is ongoing, with full operation planned for late 2015.

Accelerated partial breast irradiation: a review and evaluation of indications for treatment

Accelerated partial breast irradiation (APBI) represents a well-studied treatment modality for the delivery of adjuvant radiation therapy following breast-conserving surgery. Interstitial APBI represents the APBI technique with the longest follow-up to date; data from randomized trials and matched pair analyses demonstrate equivalent local control to traditional whole-breast irradiation with comparable rates of toxicity and improved cosmesis. While less mature, prospective data support the efficacy and safety of applicator-based brachytherapy with new multilumen applicators offering the potential for improved outcomes. External beam APBI represents a noninvasive technique; however, concerns regarding toxicity with this technique have emerged though newer techniques may mitigate these concerns. Multiple guidelines have been published based on traditional clinical and pathologic criteria to help physicians offer APBI to appropriately selected patients.

Ductal Carcinoma In Situ of the Breast: Evaluating the Role of Radiation Therapy in the Management and Attempts to Identify Low-risk Patients

Ductal carcinoma in situ of the breast has rapidly increased in incidence over the past several decades secondary to an increased use of screening mammography. Local treatment options for women diagnosed with ductal carcinoma in situ include mastectomy or breast-conserving therapy. Although several randomized trials have confirmed a >50% reduction in the risk of local recurrence with the administration of radiation therapy (RT) compared with breast-conserving surgery alone, controversy persists regarding whether or not RT is needed in selected "low-risk" patients. Over the past two decades, two prospective single-arm studies and one randomized trial have been performed and confirm that the omission of RT after surgery is associated with higher rates of local recurrence even after selecting patients with optimal clinical and pathologic features. Importantly, these trials have failed to consistently and reproducibly identify a low-risk cohort of patients (based on clinical and pathologic features) that does not benefit from RT. As a result, adjuvant RT is still advocated in the majority of patients, even in low-risk cases. Future research is moving beyond traditional clinical and pathologic risk factors and instead focusing on approaches such as multigene assays and biomarkers with the hopes of identifying truly low-risk patients who may not require RT. However, recent studies confirm that even low-risk patients identified from multigene assays have higher rates of local recurrence with local excision alone than would be expected with the addition of RT.

Accumulation of silver by Fucus spp. (Phaeophyceae) and its toxicity to Fucus ceranoides under different salinity regimes

Metals constitute an important group of abiotic stressors that elicit stress responses in marine algae that include the production of reactive oxygen species (ROS). Silver (Ag) is a highly toxic metal to organisms but despite this there are relatively few studies on how it affects marine macroalgae (seaweeds). In a landmark study published in 1977 the first information was provided on the accumulation of Ag in Fucus spp. (Phaeophyceae) from the Looe estuary, located in south-west England, an area with a long history of mining activity. In the present study, the estuary has been re-visited and the patterns of Ag accumulation in two Fucus spp. and sediment re-examined after 35 years. We conclude that Ag concentrations in sediment and macroalgae from specific sites within the catchment remain high, but more generally sediment concentrations have declined by approximately 65 % and the dissolved, bioavailable fraction by 24 % over this period. In addition, from laboratory studies we provide data on the speciation and toxic effects of Ag under different salinity regimes in the euryhaline brown seaweed, Fucus ceranoides. From these exposure experiments, it was found that with increasing Ag concentrations growth was inhibited and lipid peroxidation associated with ROS production increased. The magnitude of the toxic effects was greater at a salinity of 10 than 28 psu which reflects the greater bioavailability of the toxic species of Ag (Ag(+) and AgCl(0)) at reduced salinities. These findings emphasise the importance of investigating the effects of metal pollution in conjunction with other, natural, environmental stressors such as salinity.

Consensus statement: the 16th Annual Western Canadian Gastrointestinal Cancer Consensus Conference; Saskatoon, Saskatchewan; September 5-6, 2014

The 16th annual Western Canadian Gastrointestinal Cancer Consensus Conference was held in Saskatoon, Saskatchewan, September 4-5, 2014. The Consensus Conference is an interactive, multidisciplinary event attended by health care professionals from across western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba) involved in the care of gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; radiologists; and allied health care professionals participated in presentation and discussion sessions for the purposes of developing the recommendations presented here. This consensus statement addresses current issues in the management of colorectal cancer.

A novel surgical method of managing a high output pharyngostome

Pharyngocutaneous fistulas following large oncological surgical resection of the upper aerodigestive tract are common and typically heal over a number of weeks. A pharyngostome is a surgically created non-healing opening into the pharynx, which is far less common and often difficult to manage.

Strategies of sequential therapies in unresectable metastatic colorectal cancer: a meta-analysis

BACKGROUND

Before the emergence of first-line combination chemotherapy, the standard of care for unresectable metastatic colorectal cancer (mcrc) was first-line monotherapy with modulated 5-fluorouracil. Several large phase iii randomized controlled trials, now completed, have assessed whether a planned sequential chemotherapy strategy-beginning with fluoropyrimidine monotherapy until treatment failure, followed by another regimen (either monotherapy or combination chemotherapy) until treatment failure-could result in the same survival benefit produced with an upfront combination chemotherapy strategy, but with less toxicity for patients.

METHODS

The medline and embase databases, and abstracts from meetings of the American Society for Clinical Oncology and the European Society for Medical Oncology, were searched for reports comparing a sequential strategy of chemotherapy with an upfront combination chemotherapy in adult patients with mcrc. Publications that reported efficacy or toxicity data (or both) were included.

RESULTS

The five eligible trials that were identified included 4532 patients. A meta-analysis of those trials demonstrates a statistically significant survival advantage for combination chemotherapy (hazard ratio: 0.92; 95% confidence interval: 0.86 to 0.99). However, the median survival advantage (3-6 weeks in most trials) is small and of questionable clinical significance. Three trials reported first-line toxicities. Upfront combination chemotherapy results in significantly more neutropenia, febrile neutropenia, thrombocytopenia, diarrhea, nausea, vomiting, and sensory neuropathy. Sequential chemotherapy results in significantly more hand-foot syndrome.

CONCLUSIONS

Given the small survival advantage associated with upfront combination chemotherapy, planned sequential chemotherapy and upfront combination chemotherapy can both be considered treatment strategies. Treatment should be chosen on an individual basis considering patient and tumour characteristics, toxicity of each strategy, and patient preference.

An evidence-based approach to the management of snoring in adults

BACKGROUND

Snoring is frequently encountered by the otolaryngologist. Given its significant impact on quality of life and that it is a symptom of sleep-related breathing disorders, diagnosis and treatment are of major importance. In particular, the diagnosis should aim to distinguish between simple snoring and obstructive sleep apnoea. This article aims to provide a systematic, concise and evidence-based method of managing the adult patient with snoring.

METHOD

This review was based on a literature search last undertaken on 30 June 2014. The MEDLINE, EMBASE and Cochrane databases were searched using the subject headings snoring and obstructive sleep apnoea in adults in combination with classification, diagnosis, investigations, management, treatment and surgery. Results were limited to English language articles including case series, clinical trials, randomised controlled trials, meta-analyses, systematic reviews and review articles. Relevant references from selected articles were also reviewed.

RESULTS

The majority of published literature for snoring is of level II/III evidence and that for obstructive sleep apnoea being of level I/II, with 36 relevant randomised controlled trials identified. The diagnosis of obstructive sleep apnoea involves thorough clinical assessment and typically a sleep study. Snoring may be managed with lifestyle modification, intra-oral devices or by surgical intervention, with continuous positive airway pressure being the treatment of choice for moderate-to-severe obstructive sleep apnoea.

CONCLUSIONS

A structured history of snoring and its associated symptoms, comprehensive examination including flexible laryngoscopy and sleep studies where relevant, in addition to targeted investigations, should lead to the correct diagnosis and appropriate management.

Dose-finding results in an adaptive, seamless, randomized trial of once-weekly dulaglutide combined with metformin in type 2 diabetes patients (AWARD-5)

AIMS

AWARD-5 was an adaptive, seamless, double-blind study comparing dulaglutide, a once-weekly glucagon-like peptide-1 (GLP-1) receptor agonist, with placebo at 26 weeks and sitagliptin up to 104 weeks. The study also included a dose-finding portion whose results are presented here.

METHODS

Type 2 diabetes (T2D) patients on metformin were randomized 3 : 1 : 1 to seven dulaglutide doses, sitagliptin (100 mg), or placebo. A Bayesian algorithm was used for randomization and dose selection. Patients were adaptively randomized to dulaglutide doses using available data on the basis of a clinical utility index (CUI) of glycosylated haemoglobin A1c (HbA1c) versus sitagliptin at 52 weeks and weight, pulse rate (PR) and diastolic blood pressure (DBP) versus placebo at 26 weeks. The algorithm randomly assigned patients until two doses were selected.

RESULTS

Dulaglutide 1.5 mg was determined to be the optimal dose. Dulaglutide 0.75 mg met criteria for the second dose. Dulaglutide 1.5 mg showed the greatest Bayesian mean change from baseline (95% credible interval) in HbA1c versus sitagliptin at 52 weeks -0.63 (-0.98 to -0.20)%. Dulaglutide 2.0 mg showed the greatest placebo-adjusted mean change in weight [-1.99 (-2.88 to -1.20) kg] and in PR [0.78 (-2.10 to 3.80) bpm]. Dulaglutide 1.5 mg showed the greatest placebo-adjusted mean change in DBP [-0.62 (-3.40 to 2.30) mmHg].

CONCLUSIONS

The Bayesian algorithm allowed for an efficient exploration of a large number of doses and selected dulaglutide doses of 1.5 and 0.75 mg for further investigation in this trial.

Cardiac dose sparing and avoidance techniques in breast cancer radiotherapy

Breast cancer radiotherapy represents an essential component in the overall management of both early stage and locally advanced breast cancer. As the number of breast cancer survivors has increased, chronic sequelae of breast cancer radiotherapy become more important. While recently published data suggest a potential for an increase in cardiac events with radiotherapy, these studies do not consider the impact of newer radiotherapy techniques commonly utilized. Therefore, the purpose of this review is to evaluate cardiac dose sparing techniques in breast cancer radiotherapy. Current options for cardiac protection/avoidance include (1) maneuvers that displace the heart from the field such as coordinating the breathing cycle or through prone patient positioning, (2) technological advances such as intensity modulated radiation therapy (IMRT) or proton beam therapy (PBT), and (3) techniques that treat a smaller volume around the lumpectomy cavity such as accelerated partial breast irradiation (APBI), or intraoperative radiotherapy (IORT). While these techniques have shown promise dosimetrically, limited data on late cardiac events exist due to the difficulties of long-term follow up. Future studies are required to validate the efficacy of cardiac dose sparing techniques and may use surrogates for cardiac events such as biomarkers or perfusion imaging.

Oncology education in Canadian undergraduate and postgraduate medical programs: a survey of educators and learners

BACKGROUND

The oncology education framework currently in use in Canadian medical training programs is unknown, and the needs of learners have not been fully assessed to determine whether they are adequately prepared to manage patients with cancer.

METHODS

To assess the oncology education framework currently in use at Canadian medical schools and residency training programs for family (fm) and internal medicine (im), and to evaluate opinions about the content and utility of standard oncology education objectives, a Web survey was designed and sent to educators and learners. The survey recipients included undergraduate medical education curriculum committee members (umeccms), directors of fm and im programs, oncologists, medical students, and fm and im residents.

RESULTS

Survey responses were received from 677 educators and learners. Oncology education was felt to be inadequate in their respective programs by 58% of umeccms, 57% of fm program directors, and 50% of im program directors. For learners, oncology education was thought to be inadequate by 67% of medical students, 86% of fm residents, and 63% of im residents. When comparing teaching of medical subspecialty-related diseases, all groups agreed that their trainees were least prepared to manage patients with cancer. A standard set of oncology objectives was thought to be possibly or definitely useful for undergraduate learners by 59% of respondents overall and by 61% of postgraduate learners.

CONCLUSIONS

Oncology education in Canadian undergraduate and postgraduate fm and im training programs are currently thought to be inadequate by a majority of educators and learners. Developing a standard set of oncology objectives might address the needs of learners.

Illustrations of mathematical modeling in biology: epigenetics, meiosis, and an outlook

In the past few years, mathematical modeling approaches in biology have begun to fulfill their promise by assisting in the dissection of complex biological systems. Here, we review two recent examples of predictive mathematical modeling in plant biology. The first involves the quantitative epigenetic silencing of the floral repressor gene FLC in Arabidopsis, mediated by a Polycomb-based system. The second involves the spatiotemporal dynamics of telomere bouquet formation in wheat-rye meiosis. Although both the biology and the modeling framework of the two systems are different, both exemplify how mathematical modeling can help to accelerate discovery of the underlying mechanisms in complex biological systems. In both cases, the models that developed were relatively minimal, including only essential features, but both nevertheless yielded fundamental insights. We also briefly review the current state of mathematical modeling in biology, difficulties inherent in its application, and its potential future development.

Role of computed tomography in unsafe chronic suppurative otitis media

Thirty Patients of Unsafe chronic suppurative otitis media were subjected to pre-operative CT scanning followed by surgical exploration of the middle ear and mastoid, and their scans were compared with the peroperative data. High resolution CT scanning has been advocated for evaluation of unsafe chronic suppurative otitis media as it is capable of delineating detail required to detect Labyrinthine fistulae, Facial canal erosion, Sinus and Dural plate erosion and Ossicular integrity. Our results showed CT scan to be highly sensitive for soft tissue density mass in the middle ear and mastoid. Dural plate exposure, Sinus plate erosion, Facial canal and Stapes integrity, moderately sensitive for Malleus and Incus integrity and least sensitive for Lateral canal fistulae. Both Axial and Coronal scans were done as many important structures are best seen in only one of these planes. The principal merit of CT scan of the Tomporal bone lies in its inherent ability to depict pathology which is not clinically evident.